Direct answer
A “TDI” forex notification does not have one universal clock time that applies to all implementations. In practice, alerts are sent when a rule inside the strategy evaluates to true—typically at specific moments such as the end of a candle (bar) or when an intrabar condition is detected—according to the platform’s data update behavior.
To answer “when does it send notifications,” you need to identify two things: (1) the exact alert trigger condition (for example, “cross happens on candle close” versus “cross detected intrabar”), and (2) the evaluation schedule (for example, per tick, per minute, or once per bar).
How it works (mechanics)
Most TDI-style workflows use the TDI concept as an input indicator, then apply additional logic to decide whether to alert. The indicator values themselves update whenever the underlying price data updates, but alerts are usually gated by rules such as:
- Bar-close evaluation: the system checks conditions only when a candle closes on your chosen timeframe (for example, 15-minute candles). This makes alert timing consistent to candle boundaries.
- Intrabar evaluation: the system checks continuously while a candle is forming. This can cause multiple “would-have-triggered” moments, followed by a final outcome at close.
- Cross/threshold logic: alerts often depend on events like “a line crosses another line” or “a value moves past a level,” and the rule may specify whether the cross must be confirmed at close.
Because platforms differ, the same visual event on your chart may or may not produce an alert instantly. The most verifiable interpretation is: alerts are emitted at the moment the platform’s strategy code runs its condition checks.
Example checks to determine the real timing
Use a simple verification method that does not require guessing:
- Pick a timeframe and a known chart event. Identify a visible TDI-related event (for example, a line crossing) on your chart.
- Record the timestamp of the chart event. Note whether it occurs before candle close or at the close boundary.
- Record the alert timestamp from the platform. Compare alert time versus the event time.
- Repeat with several candles. If alerts consistently match candle closes, the system is likely bar-close gated. If alerts appear during the candle, it is likely intrabar-evaluated.
This directly answers “when” for your setup by linking alert timestamps to the chart’s candle lifecycle.
Limitations and uncertainty (what you can and cannot conclude)
There is uncertainty because “TDI” can refer to different indicator definitions and different strategy/alert rules. Also, platform settings (data source, execution model, and alert settings) can change alert timing without changing the chart visually.
Using out-of-sample testing as a concept means you verify behavior on new, unseen data windows using the same alert rules, rather than inferring timing from one chart segment. Even then, you cannot infer future alert frequency or outcomes with certainty; you only verify how the system behaved under the defined rule set and evaluation schedule.
If you want the precise answer for a specific implementation, the only dependable approach is to confirm the trigger condition and evaluation timing in the alert logic, then verify against timestamped chart events.